ProtonMail Background Image w/ Blur

pm-image-blur.css

html {
  /* Just change this image to your own. And edit the one below too. */
  background: url(https://mail.protonmail.com/assets/img/login.jpg) no-repeat center center fixed #667cbd; 
  -webkit-background-size: cover;
  -moz-background-size: cover;
  -o-background-size: cover;
  background-size: cover;
}
body #pm_main::before {
  /* Edit this image to be the same. */
  background: url(https://mail.protonmail.com/assets/img/login.jpg) no-repeat center center fixed #667cbd; 
  -webkit-background-size: cover;
  -moz-background-size: cover;
  -o-background-size: cover;
  background-size: cover;
  -webkit-filter: blur(5px);
  filter: blur(5px);
  transition-property: opacity;
  transition-duration: .55s;
  transition-timing-function: cubic-bezier(.165, .84, .44, 1);
  position: absolute;
  top: 0;
  left: 0;
  z-index: -1;
  width: 100%;
  height: 100%;
  content: "";
}
body #pm_main {
  position: relative;
  background-color: rgba(255,255,255,0.3);
  border-top-left-radius: 15px;
}
body, body #body, body header, body header a.logo, body section.sidebar, #ptSidebar {
  background: transparent !important;
}
body #conversation-list-rows .conversation.read, .conversation.read {
  background: transparent;
}
.conversation.active {
  background: #828895 !important;
}